1. Field of the Invention
The present invention relates to cooling systems for gas compressors and the like. More particularly, the present invention relates to a secondary cooling system for a gas compressor and the like for particularly cooling the packing case in the cylinder of the compressor by providing a secondary coolant within the system.
2. General Background
At the present time large gas compressors are utilized in various phases of industries, particularly in refineries, wherein gas has to be transported under compression, in lift stations for lifting gas out of the earth, or for storing gas under pressure back into the earth. This is, in most cases, accomplished by the use of a compression system whereby the gas is pumped under pressure via the use of one or more cylinders forcing the gas into storage or transport.
One of the primary concerns in the use of a gas compressor for compressing gas within the system is to make certain that the gas compressor is maintained at a reasonable temperature so that the engine which is supplying the power to the gas compressor is maintained at one temperature, that is the temperature to keep the engine running at its peak, and yet the gas compressor itself be maintained at a lower temperature so that certain elements within the compressor are not damaged due to excessive heat.
At the present time, in most cases, this requires a three-phase cooling system which provides a coolant solution to circulate through a piping system within the engine and gas compressor for cooling the engine and gas compressor at the various phases. The first phase includes a radiator, which is very common in the art, wherein the water or coolant is transported through the radiator for release of the heat into the atmosphere. Upon leaving the radiator, the water is pumped via a water pump or the like into the engine where it is transported into a series of pipes for cooling the engine. In the next phase, the water, upon leaving the engine, moves into the cylinder cooling chamber of the compressor in order to cool the cylinder. Since the cylinder area is somewhat smaller than the engine itself, the piping around the cylinder is reduced in size, which in itself contributes to overheating. Upon leaving the cylinder, the water then enters the third phase of again smaller piping for cooling the packing case around the compressor rod itself.
The packing case is comprised of a series of metal cups which encase the compressor rod between the cylinder head and the drive shaft. Within the metal cups is packing material. During the compression of the gas by the piston to the cylinder head, some of the gas is able to escape behind the piston and move along the compressor rod. In order to effectively reduce the pressure of this gas and to nullify any pressurized gas moving in that direction, the packing case serves as an obstruction for the gas as it passes through the series of metal cups with the packing material, and at the point where the gas has made it through the last cup, it simply vents out into the atmosphere, as a harmless byproduct.
However, with the movement of the compressor rod within the packing case, tremendous heat is built up. Therefore it is essential that the packing case be maintained at a relatively cool temperature. That is accomplished by the use of water or coolant flowing around the packing case for transfer of the heat within the packing case into the water. If such is not accomplished at the right temperature, the compressor rod and rod packing becomes overheated and may be damaged, causing shutdown in the compressor and loss of valuable time and manpower.
The most significant problem confronted in the present state of the art is that the cooling system for engine drive compressors is designed to maintain the water or coolant at a temperature which is adequate to cool the engine but too high to adequately cool the compressor. Therefore, the water which is routed in this multiphase system through the radiator, the engine, the cylinder and the packing case, is retrieved from the packing case at an unacceptably high temperature. As this water is simply re-routed back into the radiator, the radiator, regardless of size, is not able to cool the water down to much below that of ambient temperature resulting in unacceptably high temperature of the water. Although this temperature of the water is suitable for the cooling of the engine, since engines would tend to run at that temperature of coolant extracting heat, the temperature of the packing case must be reduced to a temperature down between 85.degree. F. and 100.degree. F. (OEM Recommendation). Since in the multi-phase system, the water upon leaving the engine goes into the cylinder and finally into the packing case, the temperature of the water is necessarily higher than recommended, and therefore, the packing case becomes overheated, and damage insues to the compressor rod and packing material.
Therefore, it is necessary that a system be developed which would provide a secondary cooling system for maintaining the water coolant at a temperature suitable for the packing case, and utilize a primary cooling system for the engine itself.
Several patents have been found which speak to the cooling system for internal combustion engines, the most pertinent being as follows:
U.S. Pat. No. 1,651,157 issued to S. W. Rushmore entitled "Cooling System" would teach the use of a cooling system for internal combustion engines having a forcefeed water circulating system of small heat disapating capacity, including a water jacket, a high level overflow outlet from the jacket, with the method being by boiling and condensing coolant.
U.S. Pat. No. 2,789,647 issued to K. W. Couse entitled "Motor Vehicle Cooling System With Auxiliary Radiator" would teach the use of an internal combustion engine having an auxiliary radiator with pipes connecting the sections of the auxiliary radiator to the main radiator to provide further cooling of the water.
U.S. Pat. No. 3,780,712 issued to Pace entitled "Marine Engine Cooling" teaches the use of an improved water jacketed manifold for marine engine cooling system wherein heated water has circulated through an engine and is mixed with an improved engine manifold water cooled by a water jacket with raw, relatively cool water for cooling the manifold and avoiding condensing water from the exhaust gases flowing through the exhaust manifold.
U.S. Pat. No. 2,887,097 issued to Huffman, Sr., et al. entitled "Supplemental Cooling System For Engine Radiators" which teach the use of a multiple radiator for helping to cool engines rather than the use of a single radiator.
U.S. Pat. No. 1,974,907 issued to Worth entitled "Engine Cooling System" would teach the use of two internal combustion engines having cooling jackets arranged for independent or simultaneously operations so as to permit mixture of the cooling medium from the two systems whereby to insure delivery of cooling medium at the same temperature to each system.
U.S. Pat. No. 2,262,659 issued to M. Ware entitled "Internal Combustion Engine" would teach the use of an engine within a power plant with circulatory fluid heat transfer systems for a pair of engines of a connection between the systems for diverting a portion of the heated fluid in either system to the other system and means for controlling the flow of fluid through the connection.
U.S. Pat. No. 1,643,510 issued to Muir entitled "Variable Temperature Cooling System For Internal Combustion Engines" would teach the combination of a water jacket, means for cooling the fluid in the jacket, means for regulating temperature to which the fluid is cool while the engine is running in a vent for permitting the escape of air from the system with a control for controlling the vent.
And U.S. Pat. No. 3,134,371 issued to Crooks entitled "Cooling System For Internal Combustion Engines" would teach a method of cooling an internal combustion engine providing a large recirculating flow of cooling fluid through the jacket in the engine and having a second cooling circuit, and maintaining the second coolant circuit at as low a temperature as possible to provide better cooling of the system.